The present invention relates to a display device in which a stopper piece for aligning a display panel is formed in a frame, a manufacturing method thereof, and an image terminal unit in which the display device is employed.
FIG. 11 is an exploded perspective view of main constituent members of a conventional liquid crystal display device.
A liquid crystal display panel 100 is connected with a circuit substrate 102 via base material films of a plurality of TCPs 101 (Tape Carrier Package) arranged in spaced apart manner at predetermined intervals. This liquid crystal display panel 100 is sandwiched between a front frame 103 and a mold frame 104 to manufacture a liquid crystal display device 105.
In the liquid crystal display device 105 having the structure described above, a positional drift in the thickness direction of the liquid crystal display panel 100 is prevented by sandwiching the liquid crystal display panel 100 between the mold frame 104 and the front frame 103. Alignment in the vertical and horizontal directions of the liquid crystal display panel 100 is implemented by stopper pieces 106 called ribs shown in FIG. 11.
However, in the liquid crystal display device, there is a problem that narrowing the annular picture frame of the front frame 103 is difficult. Particularly, recently, there has been intensified a demand of users (personal computer makers) that the picture frame of the liquid crystal display device is narrowed as much as possible and then this is mounted in a personal computer so that a useless space in an image face is eliminated so as to achieve discrimination in goods, and thus the significance of this problem has become tangible.
The problem is explained more specifically below referring to drawings. FIG. 12 is a sectional view of a part taken along the line Axe2x80x94A shown in FIG. 11 in a state where the constituent members of FIG. 11 are assembled.
The ribs 106 are integrally molded with the mold frame 104 made of polycarbonate, and it is essential to ensure a predetermined wall thickness (about 1 to 2 mm) for molding and mechanical strength of the ribs. Here, by means of the ribs 106, the alignment of the liquid crystal display panel 100 is implemented and contact interference of the TCP films 101 and the front frame 103 is avoided as shown in FIG. 12.
Since such structure is adopted, the width L of the annular picture frame of the front frame 103 extends only a distance corresponding to the wall thickness of the stopper piece (1 to 2 mm), and this is one of factors of obstruction to narrowing of the picture frame.
The present invention was made to solve the above problem, and it is a first object of the present invention to provide a display device by which the picture frame of a front frame can be narrowed.
A second object is to provide a display device in which the picture frame of a front frame can be narrowed and the precision of alignment of a display panel and a mold frame can be improved.
A third object is to provide a manufacturing method of a display device in which process of alignment work for a display panel and a mold frame can be simplified and which can cope with narrowing of the picture frame.
A fourth object is to provide an image terminal unit in which a display image face can be widened by narrowing the picture frame of a front frame.
Japanese Unexamined Patent Publication No. 61795/1997 discloses that a liquid crystal panel is fastened by a protrusion provided in a front frame. Alignment of a liquid crystal panel is implemented by the protrusion, and this point is common to a function of a stopper piece in the present invention. However, according to FIG. 1 of the Japanese Unexamined Patent Publication No. 61795/1997, a circuit substrate 2 (corresponding to a mold frame of the present invention) is not held by side end faces of a metal frame 4 (corresponding to a front frame of the present invention). Therefore, the problem of attempting to narrow the picture frame of a liquid crystal display device cannot be recognized from the content described in that publication, and means to solve a problem described in the publication is different from that of the present invention described below.
In accordance with a first aspect of the present invention, there is provided a display device comprising a front frame having an annular picture frame and having a pair of side faces and a pair of end faces provided in outer circumferential sides of the picture frame, a mold frame sandwiched by the pair of side faces and the pair of end faces, and a display panel arranged between the front frame and the mold frame, wherein stopper pieces for alignment of the display panel are formed in the side faces and the end faces.
The stopper pieces are preferably stepped portions formed by working the side faces and the end faces, ones formed by folding protrusions protruding from a root of the side faces and the end faces, or spacer members stuck on the side faces and the end faces.
The display panel might be connected to a circuit substrate via a plurality of films arranged and spaced by gaps, and the stopper pieces might be inserted into the gaps. Preferably, the gaps into which the stopper pieces are inserted are made wider than other gaps.
By the stopper pieces, not only alignment of the display panel but also the alignment of the mold frame can be implemented.
Distances between the side face and the end face and an alignment face of the stopper piece are set to 0.1 to 0.5 mm. The distances are preferably 0.3 to 0.5 mm.
As the display panel, a liquid crystal display panel, a plasma display panel, a field emission type display panel, a light emitting diode display panel, or an electroluminescent display panel is applied.
In accordance with a second aspect of the present invention, there is provided a display device comprising a front frame having an annular picture frame and having a pair of side faces and a pair of end faces provided in outer circumferential sides of the picture frame, and a display panel arranged between the front frame and a mold frame, wherein first stopper pieces for alignment of the display panel are formed in the side face and the end face, second stopper pieces for alignment of the display panel are formed in a circumference of the mold frame, and the second stopper pieces are opposed to the first stopper pieces via the display panel.
The mold frame is sandwiched by the pair of side faces and the pair of end faces.
The first stopper pieces are preferably stepped portions formed by working the side face and the end face, ones formed by folding protrusions protruding from a root of the side face and the end face, or spacer members stuck on the side face and the end face.
The display panel might be connected to a circuit substrate via a plurality of films arranged and spaced by gaps, and the first stopper pieces might be inserted into the gaps. Preferably, the gaps into which the first stopper pieces are inserted are made wider than other gaps.
By the first stopper pieces, not only alignment of the display panel but also the alignment of the mold frame can be implemented.
Distances between the side face and the end face and an alignment face of the first stopper piece are set to 0.1 to 0.5 mm. The distances are preferably 0.3 to 0.5 mm.
As the display panel, a liquid crystal display panel, a plasma display panel, a field emission type display panel, a light emitting diode display panel, or an electroluminescent display panel can be applied.
In accordance with a third aspect of the present invention, there is provided a method for manufacturing a display device comprising the steps of: superimposing a display panel on a mold frame, abutting the display panel to stopper pieces formed in the mold frame for aligning the display panel in the vertical direction and the horizontal direction, covering the display panel by the front frame, and making the display panel contact with the stopper pieces formed in the front frame.
A circuit substrate is attached to the display panel via films arranged and spaced by gaps, and it is preferable to insert the stopper pieces formed in the front frame into the gaps.
In accordance with a fourth aspect of the present invention, there is provided an image terminal unit comprising a front frame having an annular picture frame and having a pair of side faces and a pair of end faces provided in outer circumferential sides of the picture frame, a mold frame sandwiched by the pair of side faces and the pair of end faces, a display panel arranged between the front frame and the mold frame, and a case body fastening the display panel via a fasten member provided in the front frame or the mold frame, wherein stopper pieces for alignment of the display panel are formed in the side faces and the end faces.
In accordance with a fifth aspect of the present invention, there is provided image terminal unit comprising a front frame having an annular picture frame and having a pair of side faces and a pair of end faces provided in outer circumferential sides of the picture frame, a display panel arranged between the front frame and a mold frame, and a case body fastening the display panel via a fasten member provided in the front frame or the mold frame, wherein first stopper pieces for alignment of the display panel are formed in the side face and the end face, second stopper pieces for alignment of the display panel are formed in a circumference of the mold frame, and the second stopper pieces are opposed to the first stopper pieces via the display panel.
The stopper pieces are preferably stepped portions formed by working the side face and the end face, ones formed by folding protrusions protruding from the side face and the end face, or spacer members stuck on the end face and the side face.